cisco 831 on cable modem need a running config to use dhcp on both sides

Has anybody got an 831 cisco router connected to your cable modem (dhcp) and a few computers in the "Switch ports" (inside) ports. I need it to get a dhcp adrress from the cable company and also assign dhcp (i guess it could be static but dhcp would be easier... I am looking for a basic config just to connect to the internet , be able to resolve dns (to browse web) and if I had a simple running config for the cisco 831 I could add security and other fdeatures later.. It doesn't have SDM on it or CRWS... I got it on ebay.. Also how do I completly erase any existing config without deleting the IOS ( I have no access to IOS images ...got it used)
Thank You
Jeff
Savannah, GA

downsouf912,
Here is complete config including memo_tnt's part and a more detailed firewall ruleset.
You can enter it into the router by connecting via a serial terminal.
Issue "config t" without the quotes on the exec line (that is a prompt like 'router#'. if you see 'router>' then type exec)
Paste the config into your terminal.
Type "end" without the quotes to exit config mode.
Finally, type "copy run start" without quotes to save your configuration. It will prompt "Destination filename [startup-config]?", just press enter and wait for "[OK]"

I would recommend running at least version 12.4(17) or newer. Some older versions were a bit buggy and screwed up VPN passthough and such.
You can see what version you are running by typing "sh ver" at the exec ('router#') prompt.

wow, yes this was buggy hardware the first solution worked, but was not stable, the second one works 9minor modification i put sdm and 12.4(7) that i was lucky enough to find when i saw another 831 @ school (going for ccna next month) and i copied it to the tftp on my laptop, the only reason they had the 831 was fot an (easy) SDM lab, gt lucky there. Thank you very much both of you. I just wish cisco wouldn't charge $thousands$ for someone that wants to download ios to learn and make money for * their* company, oh well some times stupid rules are .meant.. .....

Thank You !
Jeff
the flash chip is not working well though, the router reoots and it happened after an incident with static electricity. I will figure out how to download the config and ios from tftp.. you can do that right?

ios 9o3sy6-mz.124-5a.bin and sdm v 2.5 , which is great it was worth getting just for sdm it slows my net speed in half because i have 12MB and its 1 10bae t wan half duplex

it worked but didnt take.. can i load it (ios) from tftp at boot time the flash is damaged think by static.
Enabling instruction cache
Reading cookie
Initializing main memory
Sizing NVRAM
Sizing flash
Exiting init
C800/SOHO series (Board ID: 29-129) platform with 81920 Kbytes of main memory

here are Rommon setting sample ,, follow it for your case .
IP_ADDRESS=10.0.101.200
IP_SUBNET_MASK=255.0.0.0
DEFAULT_GATEWAY=10.0.0.1
TFTP_SERVER=10.101.0.123
TFTP_FILE=c2800nm-entbase-mz.123-8.T11.bin
set
boot
You can check that everything is set up correctly by entering set on its own.

I did that, t this point I am pretty sure the flash (only 12mb) looks like a so-dimm but its flash, I think that i heard static electricity when i was opening it (stupid, never again)
If it were like 10-15 $ I would order it but i can''t stand the people on ebay and web sites are tryomg tp sell it for as much or MORE than the router (worth about $80 it's 10base 10 wan and 1 switch / hub of four ports that it connects with,..good...for 1996, and to learn SDM and some IOS, I got a couple 1711 , 1721 and an 831 now that i can get working for the day but when the ram goes off , it looses its setttings and needs the tftpdnld rommmonn or xmodem to upload (xmodem can be set to 115Kb it's not that bad , , I would love to order an ADSL-WIC to "practice" from home I want to become CCNP/voice

If your unit is loosing config, you may have a config too large for your nvram. I have seen that happen before on 1600 series routers... you basically have to erase the nvram. Although I can't step you through this on the 831s as I have none to test on.

Additionally, I have seen them loose their configs and randomly reboot if the ram is going bad / damaged.

BTW... a cisco contract for those 831 routers is only like $70 for the year. Then you get support and access to all the IOS firmware files. But, you are on your honor not to do bad things there.

Also, check out http://www.memoryx.net... the company is Memory Ten. They sell very good generic ram & flash for cisco routers. I always buy from them for my cisco boxes. 831 flash chips start at like $30.

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Well, it looks like I am going to have to get a new flash memory I am 99.9% sure this is the problem, its just not worth it now, i bought this "legacy" device from ebay for $90 to play around with and learn SDM for the CCNA. That I accomplished. I will look out for deals on new flash,
Thanks for the help.
Jeff

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